using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.Text;
using System.Text;

namespace QWERTYkez.Mensura.Generator;

[Generator]
public class UnitOperatorsGenerator : IIncrementalGenerator
{
    private const string AttributeName = "UnitOperatorsGenerator";

    public void Initialize(IncrementalGeneratorInitializationContext context)
    {
        // Генерируем атрибут
        context.RegisterPostInitializationOutput(ctx =>
        {
            string attributeSource = @"
namespace QWERTYkez.Mensura
{
    [System.AttributeUsage(System.AttributeTargets.Struct, AllowMultiple = false)]
    public sealed class UnitOperatorsGeneratorAttribute : System.Attribute { }
}";
            ctx.AddSource("UnitOperatorsGeneratorAttribute.g.cs", SourceText.From(attributeSource, Encoding.UTF8));
        });

        // Ищем все readonly partial record struct с атрибутом
        var structsProvider = context.SyntaxProvider
            .CreateSyntaxProvider(
                predicate: static (node, _) => IsTargetStruct(node),
                transform: static (ctx, _) => GetStructInfo(ctx))
            .Where(info => info.HasValue)
            .Select((info, _) => info!.Value)
            .Collect();

        context.RegisterSourceOutput(structsProvider, (spc, structs) =>
        {
            foreach (var structInfo in structs)
            {
                string generatedCode = GeneratePartial(structInfo);
                spc.AddSource($"{structInfo.TypeName}.Generated.g.cs", SourceText.From(generatedCode, Encoding.UTF8));
            }
        });
    }

    private static bool IsTargetStruct(SyntaxNode node)
    {
        if (node is not RecordDeclarationSyntax record)
            return false;

        // Должен быть record struct с модификаторами readonly и partial
        if (!record.Modifiers.Any(SyntaxKind.ReadOnlyKeyword) ||
            !record.Modifiers.Any(SyntaxKind.PartialKeyword) ||
            !record.Keyword.IsKind(SyntaxKind.RecordKeyword) ||
            !record.ClassOrStructKeyword.IsKind(SyntaxKind.StructKeyword))
            return false;

        // Проверяем наличие атрибута [UnitOperatorsGenerator]
        foreach (var attrList in record.AttributeLists)
            foreach (var attr in attrList.Attributes)
            {
                string name = attr.Name.ToString();
                if (name == AttributeName || name == AttributeName + "Attribute")
                    return true;
            }
        return false;
    }

    private static StructInfo? GetStructInfo(GeneratorSyntaxContext context)
    {
        var record = (RecordDeclarationSyntax)context.Node;
        var semanticModel = context.SemanticModel;
        if (semanticModel.GetDeclaredSymbol(record) is not INamedTypeSymbol typeSymbol)
            return null;

        string namespaceName = typeSymbol.ContainingNamespace?.ToString();
        if (string.IsNullOrEmpty(namespaceName))
            return null;

        return new StructInfo(namespaceName, typeSymbol.Name);
    }

    private static string GeneratePartial(StructInfo info)
    {
        string typeName = info.TypeName;
        string ns = info.Namespace;

        // Здесь должен быть полный код из вашего файла XXXXXXXXXXXX.cs
        // с заменой {typeName} на {typeName}. Для краткости приведён скелет.
        // Вы должны скопировать сюда всё содержимое вашего второго файла,
        // заменив {typeName} на {typeName}.
        string skeleton = @"
global using {typeName} = QWERTYkez.Mensura.Units.{typeName};
global using {typeName}Extensions = QWERTYkez.Mensura.Units.{typeName}Extension;
global using {typeName}Converter = QWERTYkez.Mensura.Units.{typeName}Converter;

using System.Globalization;
using System.Runtime.Serialization;

namespace QWERTYkez.Mensura.Units;

[JsonConverter(typeof({typeName}Converter))]
public readonly partial record struct {typeName} : IMensuraUnit<{typeName}>, IEquatable<{typeName}>, IMensuraUnit
{
    [JsonInclude, DataMember, JsonPropertyName(""v"")] // для JSON / EF на случай сбоев, если пробелма с _Value
    internal double Value { get => _Value; init => _Value = value; }
    double IMensuraUnit.Value { get => _Value; init => _Value = value; }
    internal readonly double _Value;
    internal {typeName}(double value) => _Value = value;

    public override int GetHashCode() => _Value.GetHashCode();
    public int CompareTo({typeName}? other) => _Value.CompareTo(other is null ? 0d : other.Value._Value);
    public int CompareTo({typeName} other) => _Value.CompareTo(other._Value);

    public bool Equals({typeName}? other) => _Value.Equals(other?._Value);


    [JsonIgnore, IgnoreDataMember] public bool IsPositive => _Value >= 0;
    [JsonIgnore, IgnoreDataMember] public bool IsGreaterThanZero => _Value > 0;
    [JsonIgnore, IgnoreDataMember] public bool IsNegative => _Value < 0;
    [JsonIgnore, IgnoreDataMember] public bool IsZero => _Value == 0;


    public static {typeName} Zero { get; } = new(0d);
    public static {typeName} Min { get; } = new(double.MinValue);
    public static {typeName} Max { get; } = new(double.MaxValue);
    public static {typeName} NegativeInfinity { get; } = new(double.NegativeInfinity);
    public static {typeName} PositiveInfinity { get; } = new(double.PositiveInfinity);


    public static bool operator ==({typeName}? T1, {typeName}? T2) => (T1 is null ? 0d : T1.Value._Value) == (T2 is null ? 0d : T2.Value._Value);
    public static bool operator !=({typeName}? T1, {typeName}? T2) => (T1 is null ? 0d : T1.Value._Value) != (T2 is null ? 0d : T2.Value._Value);

    public static bool operator <({typeName}? T1, {typeName}? T2) => (T1 is null ? 0d : T1.Value._Value) < (T2 is null ? 0d : T2.Value._Value);
    public static bool operator <=({typeName}? T1, {typeName}? T2) => (T1 is null ? 0d : T1.Value._Value) <= (T2 is null ? 0d : T2.Value._Value);
    public static bool operator >({typeName}? T1, {typeName}? T2) => (T1 is null ? 0d : T1.Value._Value) > (T2 is null ? 0d : T2.Value._Value);
    public static bool operator >=({typeName}? T1, {typeName}? T2) => (T1 is null ? 0d : T1.Value._Value) >= (T2 is null ? 0d : T2.Value._Value);


    public static {typeName} operator +({typeName} T2) => new(+T2._Value);
    public static {typeName} operator +({typeName} T1, {typeName} T2) => new(T1._Value + T2._Value);
    public static {typeName} operator -({typeName} T2) => new(-T2._Value);
    public static {typeName} operator -({typeName} T1, {typeName} T2) => new(T1._Value - T2._Value);


    // double
    public static {typeName} operator *({typeName} T1, double T2) => new(T1._Value * T2);
    public static {typeName} operator *({typeName} T1, double? T2) => T1 * (T2 ?? 0d);
    public static {typeName} operator *(double T1, {typeName} T2) => new(T1 * T2._Value);
    public static {typeName} operator *(double? T1, {typeName} T2) => (T1 ?? 0d) * T2;
    public static {typeName} operator /({typeName} T1, double T2) => new(T1._Value / T2);
    public static {typeName} operator /({typeName} T1, double? T2) => T1 / (T2 ?? 0d);
    public static double operator /({typeName} T1, {typeName} T2) => T1._Value / T2._Value;

    // sbyte
    public static {typeName} operator *({typeName} T1, sbyte T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, sbyte? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(sbyte T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(sbyte? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, sbyte T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, sbyte? T2) => T1 / T2.ToDouble();

    // short
    public static {typeName} operator *({typeName} T1, short T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, short? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(short T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(short? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, short T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, short? T2) => T1 / T2.ToDouble();

    // int
    public static {typeName} operator *({typeName} T1, int T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, int? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(int T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(int? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, int T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, int? T2) => T1 / T2.ToDouble();

    // long
    public static {typeName} operator *({typeName} T1, long T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, long? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(long T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(long? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, long T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, long? T2) => T1 / T2.ToDouble();

    // byte
    public static {typeName} operator *({typeName} T1, byte T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, byte? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(byte T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(byte? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, byte T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, byte? T2) => T1 / T2.ToDouble();

    // ushort
    public static {typeName} operator *({typeName} T1, ushort T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, ushort? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(ushort T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(ushort? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, ushort T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, ushort? T2) => T1 / T2.ToDouble();

    // uint
    public static {typeName} operator *({typeName} T1, uint T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, uint? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(uint T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(uint? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, uint T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, uint? T2) => T1 / T2.ToDouble();

    // ulong
    public static {typeName} operator *({typeName} T1, ulong T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, ulong? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(ulong T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(ulong? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, ulong T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, ulong? T2) => T1 / T2.ToDouble();

    // nint
    public static {typeName} operator *({typeName} T1, nint T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, nint? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(nint T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(nint? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, nint T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, nint? T2) => T1 / T2.ToDouble();

    // nuint
    public static {typeName} operator *({typeName} T1, nuint T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, nuint? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(nuint T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(nuint? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, nuint T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, nuint? T2) => T1 / T2.ToDouble();

    // float
    public static {typeName} operator *({typeName} T1, float T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, float? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(float T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(float? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, float T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, float? T2) => T1 / T2.ToDouble();

    // decimal
    public static {typeName} operator *({typeName} T1, decimal T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, decimal? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(decimal T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(decimal? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, decimal T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, decimal? T2) => T1 / T2.ToDouble();

#if NET7_0_OR_GREATER
    // Int128
    public static {typeName} operator *({typeName} T1, Int128 T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, Int128? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(Int128 T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(Int128? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, Int128 T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, Int128? T2) => T1 / T2.ToDouble();

    // UInt128
    public static {typeName} operator *({typeName} T1, UInt128 T2) => T1 * T2.ToDouble();
    public static {typeName} operator *({typeName} T1, UInt128? T2) => T1 * T2.ToDouble();
    public static {typeName} operator *(UInt128 T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator *(UInt128? T1, {typeName} T2) => T1.ToDouble() * T2;
    public static {typeName} operator /({typeName} T1, UInt128 T2) => T1 / T2.ToDouble();
    public static {typeName} operator /({typeName} T1, UInt128? T2) => T1 / T2.ToDouble();
#endif

    public static explicit operator {typeName}(double val) => new(val);
    public static explicit operator double({typeName} unit) => unit._Value;

    public {typeName} Abs() => new(Math.Abs(_Value));

    /// <summary>C^2 = this^2 + B^2</summary> <returns>C = (this^2 + B^2).Sqrt(2)</returns>
    public {typeName} HypFromLeg({typeName} B) => new(Math.Sqrt(_Value * _Value + B._Value * B._Value));

    /// <summary>C^2 = this^2 + B^2</summary> <returns>C = (this^2 + B^2).Sqrt(2)</returns>
    public {typeName} HypFromLeg({typeName}? B)
    {
        double b = B is null ? 0d : B.Value._Value;
        return new(Math.Sqrt(_Value * _Value + b * b));
    }

    /// <summary>C^2 = this^2 + B^2</summary> <returns>B = (C^2 - this^2).Sqrt(2)</returns>
    public {typeName} LegFromHyp({typeName} C) => new(Math.Sqrt(C._Value * C._Value - _Value * _Value));

    /// <summary>C^2 = this^2 + B^2</summary> <returns>B = (C^2 - this^2).Sqrt(2)</returns>
    public {typeName} LegFromHyp({typeName}? C)
    {
        double c = C is null ? 0d : C.Value._Value;
        return new(Math.Sqrt(c * c - _Value * _Value));
    }

    /// <summary>this^2 = A^2 + B^2</summary> <returns>B = (this^2 - A^2).Sqrt(2)</returns>
    public {typeName} LegFromLeg({typeName} A) => new(Math.Sqrt(_Value * _Value - A._Value * A._Value));

    /// <summary>this^2 = A^2 + B^2</summary> <returns>B = (this^2 - A^2).Sqrt(2)</returns>
    public {typeName} LegFromLeg({typeName}? A)
    {
        double a = A is null ? 0d : A.Value._Value;
        return new(Math.Sqrt(_Value * _Value - a * a));
    }
}

public static class {typeName}Extension
{
    internal static double ToDouble(this {typeName}? unit) => unit is null ? 0d : unit.Value._Value;

    public static {typeName} MetricSum(this IEnumerable<{typeName}> units) => new(units?.Sum(m => m._Value) ?? 0d);
    public static {typeName} MetricAverage(this IEnumerable<{typeName}> units) => new(units?.Average(m => m._Value) ?? double.NaN);
    public static {typeName} MetricMax(this IEnumerable<{typeName}> units) => new(units?.Max(m => m._Value) ?? double.MinValue);
    public static {typeName} MetricMin(this IEnumerable<{typeName}> units) => new(units?.Min(m => m._Value) ?? double.MaxValue);

    public static {typeName} MetricSum(this IEnumerable<{typeName}?> units) => new(units?.Sum(m => m.ToDouble()) ?? 0d);
    public static {typeName} MetricAverage(this IEnumerable<{typeName}?> units) => new(units?.Average(m => m.ToDouble()) ?? double.NaN);
    public static {typeName} MetricMax(this IEnumerable<{typeName}?> units) => new(units?.Max(m => m.ToDouble()) ?? double.MinValue);
    public static {typeName} MetricMin(this IEnumerable<{typeName}?> units) => new(units?.Min(m => m.ToDouble()) ?? double.MaxValue);


    internal static void MultiplyCore(ReadOnlySpan<{typeName}> source, double value, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        var vectorized_Value = new Vector<double>(value);
        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);
            var multiplied = vector * vectorized_Value;
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        for (; i < len; i++)
        {
            Unsafe.Add(ref dstRef, i) = Unsafe.Add(ref srcRef, i) * value;
        }
    }
    internal static void DivideCore(ReadOnlySpan<{typeName}> source, double divisor, Span<{typeName}> destination)
    {
        // 1. Проверка на ноль
        if (divisor == 0d || double.IsNaN(divisor))
            throw new DivideByZeroException(""Делитель не может быть равен нулю."");

        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        var vectorized_Value = new Vector<double>(divisor);
        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);
            var multiplied = vector / vectorized_Value;
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        for (; i < len; i++)
        {
            Unsafe.Add(ref dstRef, i) = Unsafe.Add(ref srcRef, i) / divisor;
        }
    }
    internal static void DivideCore(double dividend, ReadOnlySpan<{typeName}> source, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        var vectorized_Value = new Vector<double>(dividend);
        var zeroVector = Vector<double>.Zero; // Вектор из нулей для сравнения
        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);

            // БЫСТРАЯ ПРОВЕРКА: Есть ли хотя бы один 0.0 в текущем векторе?
            if (Vector.EqualsAny(vector, zeroVector))
            {
                throw new DivideByZeroException($""Обнаружен делитель, равный нулю, в районе индексов {i}..{i + vectorSize - 1}."");
            }

            var multiplied = vectorized_Value / vector;
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        // Хвостовой цикл
        for (; i < len; i++)
        {
            double divisor = Unsafe.Add(ref srcRef, i);
            if (divisor == 0.0)
            {
                throw new DivideByZeroException($""Обнаружен делитель, равный нулю, в индексе {i}."");
            }
            Unsafe.Add(ref dstRef, i) = dividend / divisor;
        }
    }
    internal static void PlusCore(ReadOnlySpan<{typeName}> source, double summand, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        var vectorized_Value = new Vector<double>(summand);
        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);
            var multiplied = vector + vectorized_Value;
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        for (; i < len; i++)
        {
            Unsafe.Add(ref dstRef, i) = Unsafe.Add(ref srcRef, i) + summand;
        }
    }
    internal static void MinusCore(ReadOnlySpan<{typeName}> source, double subtrahend, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        var vectorized_Value = new Vector<double>(subtrahend);
        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);
            var multiplied = vector - vectorized_Value;
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        for (; i < len; i++)
        {
            Unsafe.Add(ref dstRef, i) = Unsafe.Add(ref srcRef, i) - subtrahend;
        }
    }
    internal static void MinusCore(double minuend, ReadOnlySpan<{typeName}> source, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        var vectorized_Value = new Vector<double>(minuend);
        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);
            var multiplied = vectorized_Value - vector;
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        for (; i < len; i++)
        {
            Unsafe.Add(ref dstRef, i) = minuend - Unsafe.Add(ref srcRef, i);
        }
    }

    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    internal static void PowCore(ReadOnlySpan<{typeName}> source, int power, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);
        int vectorSize = Vector<double>.Count;
        int i = 0;
        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);
        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            var vector = new Vector<double>(MemoryMarshal.CreateReadOnlySpan(ref Unsafe.Add(ref srcRef, i), vectorSize));
            var resultVector = VectorPow(vector, power);
            resultVector.CopyTo(MemoryMarshal.CreateSpan(ref Unsafe.Add(ref dstRef, i), vectorSize));
        }

        // Приватный SIMD-метод быстрого возведения в степень
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static Vector<double> VectorPow(Vector<double> baseVector, int exp)
        {
            if (exp == 0) return Vector<double>.One;
            if (exp == 1) return baseVector;

            if (exp < 0)
            {
                baseVector = Vector<double>.One / baseVector;
                exp = -exp; // Внимание: может переполниться при int.Min_Value, но для степеней это редчайший кейс
            }

            var result = Vector<double>.One;
            var currentBase = baseVector;

            while (exp > 0)
            {
                if ((exp & 1) == 1)
                {
                    result *= currentBase;
                }
                currentBase *= currentBase;
                exp >>= 1;
            }

            return result;
        }

        for (; i < len; i++)
            Unsafe.Add(ref dstRef, i) = Math.Pow(Unsafe.Add(ref srcRef, i), power);
    }
    [MethodImpl(MethodImplOptions.AggressiveOptimization)]
    internal static unsafe void PowCore(ReadOnlySpan<{typeName}> source, double power, Span<{typeName}> destination)
    {
        int len = source.Length;
        if (len == 0) return;

        fixed (double* pSrc = MemoryMarshal.Cast<{typeName}, double>(source))
        fixed (double* pDst = MemoryMarshal.Cast<{typeName}, double>(destination))
        {
            double* pCurrentSrc = pSrc;
            double* pCurrentDst = pDst;
            double* pEnd = pSrc + len;

            while (pCurrentSrc <= pEnd - 4)
            {
                pCurrentDst[0] = Math.Pow(pCurrentSrc[0], power);
                pCurrentDst[1] = Math.Pow(pCurrentSrc[1], power);
                pCurrentDst[2] = Math.Pow(pCurrentSrc[2], power);
                pCurrentDst[3] = Math.Pow(pCurrentSrc[3], power);

                pCurrentSrc += 4;
                pCurrentDst += 4;
            }

            while (pCurrentSrc < pEnd)
            {
                *pCurrentDst = Math.Pow(*pCurrentSrc, power);

                pCurrentSrc++;
                pCurrentDst++;
            }
        }
    }
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    internal static void SqrtCore(ReadOnlySpan<{typeName}> source, Span<{typeName}> destination)
    {
        int len = source.Length;
        ReadOnlySpan<double> srcDouble = MemoryMarshal.Cast<{typeName}, double>(source);
        Span<double> dstDouble = MemoryMarshal.Cast<{typeName}, double>(destination);

        int vectorSize = Vector<double>.Count;
        int i = 0;

        ref double srcRef = ref MemoryMarshal.GetReference(srcDouble);
        ref double dstRef = ref MemoryMarshal.GetReference(dstDouble);

        int SIMDEnd = len - (len % vectorSize);
        for (; i < SIMDEnd; i += vectorSize)
        {
            ref double currentSrc = ref Unsafe.Add(ref srcRef, i);
            ReadOnlySpan<double> srcWindow = MemoryMarshal.CreateReadOnlySpan(ref currentSrc, vectorSize);
            var vector = new Vector<double>(srcWindow);
            var multiplied = Vector.SquareRoot(vector);
            ref double currentDst = ref Unsafe.Add(ref dstRef, i);
            Span<double> dstWindow = MemoryMarshal.CreateSpan(ref currentDst, vectorSize);
            multiplied.CopyTo(dstWindow);
        }

        for (; i < len; i++)
        {
            Unsafe.Add(ref dstRef, i) = Math.Sqrt(Unsafe.Add(ref srcRef, i));
        }
    }

    // ==========================================
    // === MULTIPLY ===
    // ==========================================

    public static {typeName}[] Multiply(this {typeName}[] units, double multiplicator)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        MultiplyCore(units, multiplicator, result);
        return result;
    }
    public static {typeName}[] Multiply(this double multiplicator, {typeName}[] units)
        => units.Multiply(multiplicator);
    public static {typeName}?[] Multiply(this {typeName}?[] units, double multiplicator)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value * multiplicator);
        }
        return result;
    }
    public static {typeName}?[] Multiply(this double multiplicator, {typeName}?[] units)
        => units.Multiply(multiplicator);

    // === ReadOnlySpan ===
    public static Span<{typeName}> Multiply(this ReadOnlySpan<{typeName}> units, double multiplicator)
    {
        if (units.Length == 0) return [];
        Span<{typeName}> result = new {typeName}[units.Length];
        MultiplyCore(units, multiplicator, result);
        return result;
    }
    public static Span<{typeName}> Multiply(this double multiplicator, ReadOnlySpan<{typeName}> units)
        => units.Multiply(multiplicator);
    public static Span<{typeName}?> Multiply(this ReadOnlySpan<{typeName}?> units, double multiplicator)
    {
        if (units.Length == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);

        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value * multiplicator);
        }
        return result;
    }
    public static Span<{typeName}?> Multiply(this double multiplicator, ReadOnlySpan<{typeName}?> units)
        => units.Multiply(multiplicator);

    // === List<Length> ===
    public static List<{typeName}> Multiply(this List<{typeName}> units, double multiplicator)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        MultiplyCore(CollectionsMarshal.AsSpan(units), multiplicator, CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}> Multiply(this double multiplicator, List<{typeName}> units)
        => units.Multiply(multiplicator);
    public static List<{typeName}?> Multiply(this List<{typeName}?> units, double multiplicator)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value * multiplicator);
        }
        return result;
    }
    public static List<{typeName}?> Multiply(this double multiplicator, List<{typeName}?> units)
        => units.Multiply(multiplicator);

    // === ICollection<Length> ===
    public static Tcoll Multiply<Tcoll>(this ICollection<{typeName}> units, double multiplicator)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item._Value * multiplicator));
        return tColl;
    }
    public static Tcoll Multiply<Tcoll>(this double multiplicator, ICollection<{typeName}> units)
        where Tcoll : class, ICollection<{typeName}>, new() => Multiply<Tcoll>(units, multiplicator);
    public static Tcoll Multiply<Tcoll>(this ICollection<{typeName}?> units, double multiplicator)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? item.Value._Value * multiplicator : 0d));
        return tColl;
    }
    public static Tcoll Multiply<Tcoll>(this double multiplicator, ICollection<{typeName}?> units)
        where Tcoll : class, ICollection<{typeName}?>, new() => Multiply<Tcoll>(units, multiplicator);

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Multiply(this IEnumerable<{typeName}> units, double multiplicator)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(item._Value * multiplicator);
    }
    public static IEnumerable<{typeName}> Multiply(this double multiplicator, IEnumerable<{typeName}> units)
        => units.Multiply(multiplicator);
    public static IEnumerable<{typeName}?> Multiply(this IEnumerable<{typeName}?> units, double multiplicator)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(item.Value._Value * multiplicator) : null;
    }
    public static IEnumerable<{typeName}?> Multiply(this double multiplicator, IEnumerable<{typeName}?> units)
        => units.Multiply(multiplicator);

    // ==========================================
    // === DIVIDE ===
    // ==========================================

    public static {typeName}[] Divide(this {typeName}[] units, double divisor)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];
        if (divisor == 0 || double.IsNaN(divisor))
            throw new ArgumentException(""Делитель не может быть 0 или NaN."", nameof(divisor));

        var result = new {typeName}[units.Length];
        DivideCore(units, divisor, result);
        return result;
    }
    public static {typeName}[] Divide(this double dividend, {typeName}[] units)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        DivideCore(dividend, units, result); // Вызов зеркального ядра (число / массив)
        return result;
    }
    public static {typeName}?[] Divide(this {typeName}?[] units, double divisor)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];
        if (divisor == 0 || double.IsNaN(divisor)) throw new ArgumentException(""Делитель не может быть 0 или NaN."", nameof(divisor));

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value / divisor);
        }
        return result;
    }
    public static {typeName}?[] Divide(this double dividend, {typeName}?[] units)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(dividend / item.Value._Value);
        }
        return result;
    }

    // === ReadOnlySpan ===
    public static Span<{typeName}> Divide(this ReadOnlySpan<{typeName}> units, double divisor)
    {
        if (units.Length == 0) return [];
        if (divisor == 0 || double.IsNaN(divisor)) throw new ArgumentException(""Делитель не может быть 0 или NaN."", nameof(divisor));
        var result = new {typeName}[units.Length];
        DivideCore(units, divisor, result);
        return result;
    }
    public static Span<{typeName}> Divide(this double dividend, ReadOnlySpan<{typeName}> units)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        DivideCore(dividend, units, result);
        return result;
    }
    public static Span<{typeName}?> Divide(this ReadOnlySpan<{typeName}?> units, double divisor)
    {
        if (units.Length == 0) return [];
        if (divisor == 0 || double.IsNaN(divisor))
            throw new ArgumentException(""Делитель не может быть 0 или NaN."", nameof(divisor));

        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);

        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value / divisor);
        }
        return result;
    }
    public static Span<{typeName}?> Divide(this double dividend, ReadOnlySpan<{typeName}?> units)
    {
        if (units.Length == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);

        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(dividend / item.Value._Value);
        }
        return result;
    }

    // === List<Length> ===
    public static List<{typeName}> Divide(this List<{typeName}> units, double divisor)
    {
        if (units is null) return null!;
        if (divisor == 0 || double.IsNaN(divisor)) throw new ArgumentException(""Делитель не может быть 0 или NaN."", nameof(divisor));
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        DivideCore(CollectionsMarshal.AsSpan(units), divisor, CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}> Divide(this double dividend, List<{typeName}> units)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        DivideCore(dividend, CollectionsMarshal.AsSpan(units), CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}?> Divide(this List<{typeName}?> units, double divisor)
    {
        if (units is null) return null!;
        if (divisor == 0 || double.IsNaN(divisor)) throw new ArgumentException(""Делитель не может быть 0 или NaN."", nameof(divisor));
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value / divisor);
        }
        return result;
    }
    public static List<{typeName}?> Divide(this double dividend, List<{typeName}?> units)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(dividend / item.Value._Value);
        }
        return result;
    }

    // === ICollection<Length> ===
    public static Tcoll Divide<Tcoll>(this ICollection<{typeName}> units, double divisor)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item._Value / divisor));
        return tColl;
    }
    public static Tcoll Divide<Tcoll>(this double dividend, ICollection<{typeName}> units)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(dividend / item._Value));
        return tColl;
    }
    public static Tcoll Divide<Tcoll>(this ICollection<{typeName}?> units, double divisor)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? item.Value._Value / divisor : 0d));
        return tColl;
    }
    public static Tcoll Divide<Tcoll>(this double dividend, ICollection<{typeName}?> units)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? dividend / item.Value._Value : 0d));
        return tColl;
    }

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Divide(this IEnumerable<{typeName}> units, double divisor)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(item._Value * divisor);
    }
    public static IEnumerable<{typeName}> Divide(this double dividend, IEnumerable<{typeName}> units)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(dividend / item._Value);
    }
    public static IEnumerable<{typeName}?> Divide(this IEnumerable<{typeName}?> units, double divisor)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(item.Value._Value * divisor) : null;
    }
    public static IEnumerable<{typeName}?> Divide(this double dividend, IEnumerable<{typeName}?> units)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(dividend / item.Value._Value) : null;
    }

    // ==========================================
    // === PLUS ===
    // ==========================================

    public static {typeName}[] Plus(this {typeName}[] units, double summand)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        PlusCore(units, summand, result);
        return result;
    }
    public static {typeName}[] Plus(this double summand, {typeName}[] units)
        => units.Plus(summand);
    public static {typeName}?[] Plus(this {typeName}?[] units, double summand)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value + summand);
        }
        return result;
    }
    public static {typeName}?[] Plus(this double summand, {typeName}?[] units)
        => units.Plus(summand);

    // === ReadOnlySpan ===
    public static Span<{typeName}> Plus(this ReadOnlySpan<{typeName}> units, double summand)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        PlusCore(units, summand, result);
        return result;
    }
    public static Span<{typeName}> Plus(this double summand, ReadOnlySpan<{typeName}> units)
        => units.Plus(summand);
    public static Span<{typeName}?> Plus(this ReadOnlySpan<{typeName}?> units, double summand)
    {
        if (units.Length == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);

        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value + summand);
        }
        return result;
    }
    public static Span<{typeName}?> Plus(this double summand, ReadOnlySpan<{typeName}?> units)
        => units.Multiply(summand);

    // === List<Length> ===
    public static List<{typeName}> Plus(this List<{typeName}> units, double summand)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        PlusCore(CollectionsMarshal.AsSpan(units), summand, CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}> Plus(this double summand, List<{typeName}> units)
        => units.Plus(summand);
    public static List<{typeName}?> Plus(this List<{typeName}?> units, double summand)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value + summand);
        }
        return result;
    }
    public static List<{typeName}?> Plus(this double summand, List<{typeName}?> units)
        => units.Plus(summand);

    // === ICollection<Length> ===
    public static Tcoll Plus<Tcoll>(this ICollection<{typeName}> units, double summand)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item._Value + summand));
        return tColl;
    }
    public static Tcoll Plus<Tcoll>(this double summand, ICollection<{typeName}> units)
        where Tcoll : class, ICollection<{typeName}>, new() => Plus<Tcoll>(units, summand);
    public static Tcoll Plus<Tcoll>(this ICollection<{typeName}?> units, double summand)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? item.Value._Value + summand : 0d));
        return tColl;
    }
    public static Tcoll Plus<Tcoll>(this double summand, ICollection<{typeName}?> units)
        where Tcoll : class, ICollection<{typeName}?>, new() => Plus<Tcoll>(units, summand);

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Plus(this IEnumerable<{typeName}> units, double summand)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(item._Value + summand);
    }
    public static IEnumerable<{typeName}> Plus(this double summand, IEnumerable<{typeName}> units)
        => units.Plus(summand);
    public static IEnumerable<{typeName}?> Plus(this IEnumerable<{typeName}?> units, double summand)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(item.Value._Value + summand) : null;
    }
    public static IEnumerable<{typeName}?> Plus(this double summand, IEnumerable<{typeName}?> units)
        => units.Plus(summand);

    // ==========================================
    // === MINUS ===
    // ==========================================

    public static {typeName}[] Minus(this {typeName}[] units, double subtrahend)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        MinusCore(units, subtrahend, result);
        return result;
    }
    public static {typeName}[] Minus(this double minuend, {typeName}[] units)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        MinusCore(minuend, units, result); // Вызов зеркального ядра (число - массив)
        return result;
    }
    public static {typeName}?[] Minus(this {typeName}?[] units, double subtrahend)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value - subtrahend);
        }
        return result;
    }
    public static {typeName}?[] Minus(this double minuend, {typeName}?[] units)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(minuend - item.Value._Value);
        }
        return result;
    }

    // === ReadOnlySpan ===
    public static Span<{typeName}> Minus(this ReadOnlySpan<{typeName}> units, double subtrahend)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        MinusCore(units, subtrahend, result);
        return result;
    }
    public static Span<{typeName}> Minus(this double minuend, ReadOnlySpan<{typeName}> units)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        MinusCore(minuend, units, result);
        return result;
    }
    public static Span<{typeName}?> Minus(this ReadOnlySpan<{typeName}?> units, double subtrahend)
    {
        if (units.Length == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);

        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value - subtrahend);
        }
        return result;
    }
    public static Span<{typeName}?> Minus(this double minuend, ReadOnlySpan<{typeName}?> units)
    {
        if (units.Length == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);

        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(minuend - item.Value._Value);
        }
        return result;
    }

    // === List<Length> ===
    public static List<{typeName}> Minus(this List<{typeName}> units, double subtrahend)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        MinusCore(CollectionsMarshal.AsSpan(units), subtrahend, CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}> Minus(this double minuend, List<{typeName}> units)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        MinusCore(minuend, CollectionsMarshal.AsSpan(units), CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}?> Minus(this List<{typeName}?> units, double subtrahend)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value - subtrahend);
        }
        return result;
    }
    public static List<{typeName}?> Minus(this double minuend, List<{typeName}?> units)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(minuend - item.Value._Value);
        }
        return result;
    }

    // === ICollection<Length> ===
    public static Tcoll Minus<Tcoll>(this ICollection<{typeName}> units, double subtrahend)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item._Value - subtrahend));
        return tColl;
    }
    public static Tcoll Minus<Tcoll>(this double minuend, ICollection<{typeName}> units)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(minuend - item._Value));
        return tColl;
    }
    public static Tcoll Minus<Tcoll>(this ICollection<{typeName}?> units, double subtrahend)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? item.Value._Value - subtrahend : 0d));
        return tColl;
    }
    public static Tcoll Minus<Tcoll>(this double minuend, ICollection<{typeName}?> units)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? minuend - item.Value._Value : 0d));
        return tColl;
    }

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Minus(this IEnumerable<{typeName}> units, double subtrahend)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(item._Value - subtrahend);
    }
    public static IEnumerable<{typeName}> Minus(this double minuend, IEnumerable<{typeName}> units)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(minuend - item._Value);
    }
    public static IEnumerable<{typeName}?> Minus(this IEnumerable<{typeName}?> units, double subtrahend)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(item.Value._Value - subtrahend) : null;
    }
    public static IEnumerable<{typeName}?> Minus(this double minuend, IEnumerable<{typeName}?> units)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(minuend - item.Value._Value) : null;
    }

    // ==========================================
    // ЦЕЛАЯ СТЕПЕНЬ (int power)
    // ==========================================

    public static {typeName}[] Pow(this {typeName}[] units, int power)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        PowCore(units, power, result);
        return result;
    }
    public static {typeName}?[] Pow(this {typeName}?[] units, int power)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue)
            {
                // Используем тот же быстрый QuickPow, что и в ядре, чтобы не вызывать тяжелый Math.Pow
                item = new {typeName}(item.Value._Value.QuickPow(power));
            }
        }
        return result;
    }

    // === ReadOnlySpan ===
    public static Span<{typeName}> Pow(this ReadOnlySpan<{typeName}> units, int power)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        PowCore(units, power, result);
        return result;
    }
    public static Span<{typeName}?> Pow(this ReadOnlySpan<{typeName}?> units, int power)
    {
        int len = units.Length;
        if (len == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value.QuickPow(power));
        }
        return result;
    }

    // === List<Length> ===
    public static List<{typeName}> Pow(this List<{typeName}> units, int power)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        PowCore(CollectionsMarshal.AsSpan(units), power, CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}?> Pow(this List<{typeName}?> units, int power)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(item.Value._Value.QuickPow(power));
        }
        return result;
    }

    // === ICollection<Length> ===
    public static Tcoll Pow<Tcoll>(this ICollection<{typeName}> units, int power)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item._Value.QuickPow(power)));
        return tColl;
    }
    public static Tcoll Pow<Tcoll>(this ICollection<{typeName}?> units, int power)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? item.Value._Value.QuickPow(power) : 0d));
        return tColl;
    }

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Pow(this IEnumerable<{typeName}> units, int power)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(item._Value.QuickPow(power));
    }
    public static IEnumerable<{typeName}?> Pow(this IEnumerable<{typeName}?> units, int power)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(item.Value._Value.QuickPow(power)) : null;
    }

    // ==========================================
    // ДРОБНАЯ СТЕПЕНЬ (double power)
    // ==========================================

    public static {typeName}[] Pow(this {typeName}[] units, double power)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        PowCore(units, power, result);
        return result;
    }
    public static {typeName}?[] Pow(this {typeName}?[] units, double power)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue)
            {
                item = new {typeName}(Math.Pow(item.Value._Value, power));
            }
        }
        return result;
    }

    // === ReadOnlySpan ===
    public static Span<{typeName}> Pow(this ReadOnlySpan<{typeName}> units, double power)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        PowCore(units, power, result);
        return result;
    }
    public static Span<{typeName}?> Pow(this ReadOnlySpan<{typeName}?> units, double power)
    {
        int len = units.Length;
        if (len == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(Math.Pow(item.Value._Value, power));
        }
        return result;
    }

    // === List<Length> ===
    public static List<{typeName}> Pow(this List<{typeName}> units, double power)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        PowCore(CollectionsMarshal.AsSpan(units), power, CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}?> Pow(this List<{typeName}?> units, double power)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(Math.Pow(item.Value._Value, power));
        }
        return result;
    }

    // === ICollection<Length> ===
    public static Tcoll Pow<Tcoll>(this ICollection<{typeName}> units, double power)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(Math.Pow(item._Value, power)));
        return tColl;
    }
    public static Tcoll Pow<Tcoll>(this ICollection<{typeName}?> units, double power)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? Math.Pow(item.Value._Value, power) : 0d));
        return tColl;
    }

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Pow(this IEnumerable<{typeName}> units, double power)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(Math.Pow(item._Value, power));
    }
    public static IEnumerable<{typeName}?> Pow(this IEnumerable<{typeName}?> units, double power)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(Math.Pow(item.Value._Value, power)) : null;
    }


    // ==========================================
    // КВАДРАТНЫЙ КОРЕНЬ (Sqrt)
    // ==========================================

    public static {typeName}[] Sqrt(this {typeName}[] units)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = new {typeName}[units.Length];
        SqrtCore(units, result);
        return result;
    }
    public static {typeName}?[] Sqrt(this {typeName}?[] units)
    {
        if (units is null) return null!;
        if (units.Length == 0) return [];

        var result = ({typeName}?[])units.Clone();
        int len = result.Length;
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue)
            {
                item = new {typeName}(Math.Sqrt(item.Value._Value));
            }
        }
        return result;
    }

    // === ReadOnlySpan ===
    public static Span<{typeName}> Sqrt(this ReadOnlySpan<{typeName}> units)
    {
        if (units.Length == 0) return [];
        var result = new {typeName}[units.Length];
        SqrtCore(units, result);
        return result;
    }
    public static Span<{typeName}?> Sqrt(this ReadOnlySpan<{typeName}?> units)
    {
        int len = units.Length;
        if (len == 0) return [];
        Span<{typeName}?> result = new {typeName}?[units.Length];
        units.CopyTo(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref result[i];
            if (item.HasValue) item = new {typeName}(Math.Sqrt(item.Value._Value));
        }
        return result;
    }

    // === List<Length> ===
    public static List<{typeName}> Sqrt(this List<{typeName}> units)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}>(len);
        result.SetCountUnsafe(len);
        SqrtCore(CollectionsMarshal.AsSpan(units), CollectionsMarshal.AsSpan(result));
        return result;
    }
    public static List<{typeName}?> Sqrt(this List<{typeName}?> units)
    {
        if (units is null) return null!;
        int len = units.Count;
        if (len == 0) return [];

        var result = new List<{typeName}?>(units);
        Span<{typeName}?> dstSpan = CollectionsMarshal.AsSpan(result);
        for (int i = 0; i < len; i++)
        {
            ref var item = ref dstSpan[i];
            if (item.HasValue) item = new {typeName}(Math.Sqrt(item.Value._Value));
        }
        return result;
    }

    // === ICollection<Length> ===
    public static Tcoll Pow<Tcoll>(this ICollection<{typeName}> units)
        where Tcoll : class, ICollection<{typeName}>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(Math.Sqrt(item._Value)));
        return tColl;
    }
    public static Tcoll Pow<Tcoll>(this ICollection<{typeName}?> units)
        where Tcoll : class, ICollection<{typeName}?>, new()
    {
        if (units is null) return null!;
        var tColl = new Tcoll();
        if (tColl is List<{typeName}> list)
            list.Capacity = units.Count;
        foreach (var item in units)
            tColl.Add(new {typeName}(item.HasValue ? Math.Sqrt(item.Value._Value) : 0d));
        return tColl;
    }

    // === IEnumerable<Length> ===
    public static IEnumerable<{typeName}> Pow(this IEnumerable<{typeName}> units)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return new {typeName}(Math.Sqrt(item._Value));
    }
    public static IEnumerable<{typeName}?> Pow(this IEnumerable<{typeName}?> units)
    {
        ArgumentNullException.ThrowIfNull(units);
        foreach (var item in units)
            yield return item.HasValue
                ? new {typeName}(Math.Sqrt(item.Value._Value)) : null;
    }
}

public class {typeName}Converter : JsonConverter<{typeName}>
{
    // Используем инвариантную культуру, чтобы разделителем всегда была точка (10.5, а не 10,5)
    private static readonly CultureInfo Culture = CultureInfo.InvariantCulture;

    public override {typeName} Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
    {
        double double_Value;

        if (reader.TokenType == JsonTokenType.String)
        {
            // Безопасно парсим double из строки с поддержкой точки как разделителя
            if (!double.TryParse(reader.GetString(), NumberStyles.Float, Culture, out double_Value))
            {
                throw new JsonException($""Не удалось преобразовать строковое значение в double для метрики {nameof({typeName})}."");
            }
        }
        else
        {
            // Прямое быстрое чтение числа из JSON
            double_Value = reader.GetDouble();
        }

        return new(double_Value);
    }

    public override void Write(Utf8JsonWriter writer, {typeName} value, JsonSerializerOptions options)
    {
        // Записываем число напрямую в байтовый буфер без выделения памяти под строки
        writer.WriteNumberValue(value._Value);
    }

    public override void WriteAsPropertyName(Utf8JsonWriter writer, {typeName} value, JsonSerializerOptions options)
    {
        // Ключи JSON-объектов всегда должны быть строками.
        // Форматируем double в строку с точкой, чтобы другие сервисы экосистемы прочитали её корректно.
        // Формат ""R"" (Round-trip) гарантирует, что число не потеряет точность при обратном парсинге.
        writer.WritePropertyName(value._Value.ToString(""R"", Culture));
    }

    public override {typeName} ReadAsPropertyName(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
    {
        string propertyName = reader.GetString()!;

        if (!double.TryParse(propertyName, NumberStyles.Float, Culture, out double double_Value))
        {
            throw new JsonException($""Невалидное числовое значение в ключе свойства JSON: '{propertyName}' для метрики {nameof({typeName})}."");
        }

        return new(double_Value);
    }
}
";
        return skeleton.Replace("{typeName}", typeName).Replace("{ns}", ns);
    }

    private readonly struct StructInfo(string ns, string name)
    {
        public string Namespace { get; } = ns;
        public string TypeName { get; } = name;
    }
}